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<div class="hidden name"><code>dimethenamid_2018.rmd</code></div> - - </div> - - - -<p><a href="http://www.jrwb.de" class="external-link">Wissenschaftlicher Berater, Kronacher -Str. 12, 79639 Grenzach-Wyhlen, Germany</a></p> -<div class="section level2"> -<h2 id="introduction">Introduction<a class="anchor" aria-label="anchor" href="#introduction"></a> -</h2> -<p>A first analysis of the data analysed here was presented in a recent -journal article on nonlinear mixed-effects models in degradation -kinetics <span class="citation">(Ranke et al. 2021)</span>. That -analysis was based on the <code>nlme</code> package and a development -version of the <code>saemix</code> package that was unpublished at the -time. Meanwhile, version 3.0 of the <code>saemix</code> package is -available from the CRAN repository. Also, it turned out that there was -an error in the handling of the Borstel data in the mkin package at the -time, leading to the duplication of a few data points from that soil. -The dataset in the mkin package has been corrected, and the interface to -<code>saemix</code> in the mkin package has been updated to use the -released version.</p> -<p>This vignette is intended to present an up to date analysis of the -data, using the corrected dataset and released versions of -<code>mkin</code> and <code>saemix</code>.</p> -</div> -<div class="section level2"> -<h2 id="data">Data<a class="anchor" aria-label="anchor" href="#data"></a> -</h2> -<p>Residue data forming the basis for the endpoints derived in the -conclusion on the peer review of the pesticide risk assessment of -dimethenamid-P published by the European Food Safety Authority (EFSA) in -2018 <span class="citation">(EFSA 2018)</span> were transcribed from the -risk assessment report <span class="citation">(Rapporteur Member State -Germany, Co-Rapporteur Member State Bulgaria 2018)</span> which can be -downloaded from the Open EFSA repository <a href="https://open.efsa.europa.eu" class="external-link">https://open.efsa.europa.eu/study-inventory/EFSA-Q-2014-00716</a>.</p> -<p>The data are <a href="https://pkgdown.jrwb.de/mkin/reference/dimethenamid_2018.html">available -in the mkin package</a>. The following code (hidden by default, please -use the button to the right to show it) treats the data available for -the racemic mixture dimethenamid (DMTA) and its enantiomer -dimethenamid-P (DMTAP) in the same way, as no difference between their -degradation behaviour was identified in the EU risk assessment. The -observation times of each dataset are multiplied with the corresponding -normalisation factor also available in the dataset, in order to make it -possible to describe all datasets with a single set of parameters.</p> -<p>Also, datasets observed in the same soil are merged, resulting in -dimethenamid (DMTA) data from six soils.</p> -<div class="sourceCode" id="cb1"><pre class="downlit sourceCode r"> -<code class="sourceCode R"><span><span class="kw"><a href="https://rdrr.io/r/base/library.html" class="external-link">library</a></span><span class="op">(</span><span class="va"><a href="https://pkgdown.jrwb.de/mkin/">mkin</a></span>, quietly <span class="op">=</span> <span class="cn">TRUE</span><span class="op">)</span></span> -<span><span class="va">dmta_ds</span> <span class="op"><-</span> <span class="fu"><a href="https://rdrr.io/r/base/lapply.html" class="external-link">lapply</a></span><span class="op">(</span><span class="fl">1</span><span class="op">:</span><span class="fl">7</span>, <span class="kw">function</span><span class="op">(</span><span class="va">i</span><span class="op">)</span> <span class="op">{</span></span> -<span> <span class="va">ds_i</span> <span class="op"><-</span> <span class="va">dimethenamid_2018</span><span class="op">$</span><span class="va">ds</span><span class="op">[[</span><span class="va">i</span><span class="op">]</span><span class="op">]</span><span class="op">$</span><span class="va">data</span></span> -<span> <span class="va">ds_i</span><span class="op">[</span><span class="va">ds_i</span><span class="op">$</span><span class="va">name</span> <span class="op">==</span> <span class="st">"DMTAP"</span>, <span class="st">"name"</span><span class="op">]</span> <span class="op"><-</span> <span class="st">"DMTA"</span></span> -<span> <span class="va">ds_i</span><span class="op">$</span><span class="va">time</span> <span class="op"><-</span> <span class="va">ds_i</span><span class="op">$</span><span class="va">time</span> <span class="op">*</span> <span class="va">dimethenamid_2018</span><span class="op">$</span><span class="va">f_time_norm</span><span class="op">[</span><span class="va">i</span><span class="op">]</span></span> -<span> <span class="va">ds_i</span></span> -<span><span class="op">}</span><span class="op">)</span></span> -<span><span class="fu"><a href="https://rdrr.io/r/base/names.html" class="external-link">names</a></span><span class="op">(</span><span class="va">dmta_ds</span><span class="op">)</span> <span class="op"><-</span> <span class="fu"><a href="https://rdrr.io/r/base/lapply.html" class="external-link">sapply</a></span><span class="op">(</span><span class="va">dimethenamid_2018</span><span class="op">$</span><span class="va">ds</span>, <span class="kw">function</span><span class="op">(</span><span class="va">ds</span><span class="op">)</span> <span class="va">ds</span><span class="op">$</span><span class="va">title</span><span class="op">)</span></span> -<span><span class="va">dmta_ds</span><span class="op">[[</span><span class="st">"Elliot"</span><span class="op">]</span><span class="op">]</span> <span class="op"><-</span> <span class="fu"><a href="https://rdrr.io/r/base/cbind.html" class="external-link">rbind</a></span><span class="op">(</span><span class="va">dmta_ds</span><span class="op">[[</span><span class="st">"Elliot 1"</span><span class="op">]</span><span class="op">]</span>, <span class="va">dmta_ds</span><span class="op">[[</span><span class="st">"Elliot 2"</span><span class="op">]</span><span class="op">]</span><span class="op">)</span></span> -<span><span class="va">dmta_ds</span><span class="op">[[</span><span class="st">"Elliot 1"</span><span class="op">]</span><span class="op">]</span> <span class="op"><-</span> <span class="cn">NULL</span></span> -<span><span class="va">dmta_ds</span><span class="op">[[</span><span class="st">"Elliot 2"</span><span class="op">]</span><span class="op">]</span> <span class="op"><-</span> <span class="cn">NULL</span></span></code></pre></div> -</div> -<div class="section level2"> -<h2 id="parent-degradation">Parent degradation<a class="anchor" aria-label="anchor" href="#parent-degradation"></a> -</h2> -<p>We evaluate the observed degradation of the parent compound using -simple exponential decline (SFO) and biexponential decline (DFOP), using -constant variance (const) and a two-component variance (tc) as error -models.</p> -<div class="section level3"> -<h3 id="separate-evaluations">Separate evaluations<a class="anchor" aria-label="anchor" href="#separate-evaluations"></a> -</h3> -<p>As a first step, to get a visual impression of the fit of the -different models, we do separate evaluations for each soil using the -mmkin function from the mkin package:</p> -<div class="sourceCode" id="cb2"><pre class="downlit sourceCode r"> -<code class="sourceCode R"><span><span class="va">f_parent_mkin_const</span> <span class="op"><-</span> <span class="fu"><a href="../../reference/mmkin.html">mmkin</a></span><span class="op">(</span><span class="fu"><a href="https://rdrr.io/r/base/c.html" class="external-link">c</a></span><span class="op">(</span><span class="st">"SFO"</span>, <span class="st">"DFOP"</span><span class="op">)</span>, <span class="va">dmta_ds</span>,</span> -<span> error_model <span class="op">=</span> <span class="st">"const"</span>, quiet <span class="op">=</span> <span class="cn">TRUE</span><span class="op">)</span></span> -<span><span class="va">f_parent_mkin_tc</span> <span class="op"><-</span> <span class="fu"><a href="../../reference/mmkin.html">mmkin</a></span><span class="op">(</span><span class="fu"><a href="https://rdrr.io/r/base/c.html" class="external-link">c</a></span><span class="op">(</span><span class="st">"SFO"</span>, <span class="st">"DFOP"</span><span class="op">)</span>, <span class="va">dmta_ds</span>,</span> -<span> error_model <span class="op">=</span> <span class="st">"tc"</span>, quiet <span class="op">=</span> <span class="cn">TRUE</span><span class="op">)</span></span></code></pre></div> -<p>The plot of the individual SFO fits shown below suggests that at -least in some datasets the degradation slows down towards later time -points, and that the scatter of the residuals error is smaller for -smaller values (panel to the right):</p> -<div class="sourceCode" id="cb3"><pre class="downlit sourceCode r"> -<code class="sourceCode R"><span><span class="fu"><a href="https://rdrr.io/r/base/plot.html" class="external-link">plot</a></span><span class="op">(</span><span class="fu"><a href="../../reference/mixed.html">mixed</a></span><span class="op">(</span><span class="va">f_parent_mkin_const</span><span class="op">[</span><span class="st">"SFO"</span>, <span class="op">]</span><span class="op">)</span><span class="op">)</span></span></code></pre></div> -<p><img src="dimethenamid_2018_files/figure-html/f_parent_mkin_sfo_const-1.png" width="700"></p> -<p>Using biexponential decline (DFOP) results in a slightly more random -scatter of the residuals:</p> -<div class="sourceCode" id="cb4"><pre class="downlit sourceCode r"> -<code class="sourceCode R"><span><span class="fu"><a href="https://rdrr.io/r/base/plot.html" class="external-link">plot</a></span><span class="op">(</span><span class="fu"><a href="../../reference/mixed.html">mixed</a></span><span class="op">(</span><span class="va">f_parent_mkin_const</span><span class="op">[</span><span class="st">"DFOP"</span>, <span class="op">]</span><span class="op">)</span><span class="op">)</span></span></code></pre></div> -<p><img src="dimethenamid_2018_files/figure-html/f_parent_mkin_dfop_const-1.png" width="700"></p> -<p>The population curve (bold line) in the above plot results from -taking the mean of the individual transformed parameters, i.e. of log k1 -and log k2, as well as of the logit of the g parameter of the DFOP -model). Here, this procedure does not result in parameters that -represent the degradation well, because in some datasets the fitted -value for k2 is extremely close to zero, leading to a log k2 value that -dominates the average. This is alleviated if only rate constants that -pass the t-test for significant difference from zero (on the -untransformed scale) are considered in the averaging:</p> -<div class="sourceCode" id="cb5"><pre class="downlit sourceCode r"> -<code class="sourceCode R"><span><span class="fu"><a href="https://rdrr.io/r/base/plot.html" class="external-link">plot</a></span><span class="op">(</span><span class="fu"><a href="../../reference/mixed.html">mixed</a></span><span class="op">(</span><span class="va">f_parent_mkin_const</span><span class="op">[</span><span class="st">"DFOP"</span>, <span class="op">]</span><span class="op">)</span>, test_log_parms <span class="op">=</span> <span class="cn">TRUE</span><span class="op">)</span></span></code></pre></div> -<p><img src="dimethenamid_2018_files/figure-html/f_parent_mkin_dfop_const_test-1.png" width="700"></p> -<p>While this is visually much more satisfactory, such an average -procedure could introduce a bias, as not all results from the individual -fits enter the population curve with the same weight. This is where -nonlinear mixed-effects models can help out by treating all datasets -with equally by fitting a parameter distribution model together with the -degradation model and the error model (see below).</p> -<p>The remaining trend of the residuals to be higher for higher -predicted residues is reduced by using the two-component error -model:</p> -<div class="sourceCode" id="cb6"><pre class="downlit sourceCode r"> -<code class="sourceCode R"><span><span class="fu"><a href="https://rdrr.io/r/base/plot.html" class="external-link">plot</a></span><span class="op">(</span><span class="fu"><a href="../../reference/mixed.html">mixed</a></span><span class="op">(</span><span class="va">f_parent_mkin_tc</span><span class="op">[</span><span class="st">"DFOP"</span>, <span class="op">]</span><span class="op">)</span>, test_log_parms <span class="op">=</span> <span class="cn">TRUE</span><span class="op">)</span></span></code></pre></div> -<p><img src="dimethenamid_2018_files/figure-html/f_parent_mkin_dfop_tc_test-1.png" width="700"></p> -<p>However, note that in the case of using this error model, the fits to -the Flaach and BBA 2.3 datasets appear to be ill-defined, indicated by -the fact that they did not converge:</p> -<div class="sourceCode" id="cb7"><pre class="downlit sourceCode r"> -<code class="sourceCode R"><span><span class="fu"><a href="https://rdrr.io/r/base/print.html" class="external-link">print</a></span><span class="op">(</span><span class="va">f_parent_mkin_tc</span><span class="op">[</span><span class="st">"DFOP"</span>, <span class="op">]</span><span class="op">)</span></span></code></pre></div> -<pre><code><mmkin> object -Status of individual fits: - - dataset -model Calke Borstel Flaach BBA 2.2 BBA 2.3 Elliot - DFOP OK OK C OK C OK - -C: Optimisation did not converge: -iteration limit reached without convergence (10) -OK: No warnings</code></pre> -</div> -<div class="section level3"> -<h3 id="nonlinear-mixed-effects-models">Nonlinear mixed-effects models<a class="anchor" aria-label="anchor" href="#nonlinear-mixed-effects-models"></a> -</h3> -<p>Instead of taking a model selection decision for each of the -individual fits, we fit nonlinear mixed-effects models (using different -fitting algorithms as implemented in different packages) and do model -selection using all available data at the same time. In order to make -sure that these decisions are not unduly influenced by the type of -algorithm used, by implementation details or by the use of wrong control -parameters, we compare the model selection results obtained with -different R packages, with different algorithms and checking control -parameters.</p> -<div class="section level4"> -<h4 id="nlme">nlme<a class="anchor" aria-label="anchor" href="#nlme"></a> -</h4> -<p>The nlme package was the first R extension providing facilities to -fit nonlinear mixed-effects models. We would like to do model selection -from all four combinations of degradation models and error models based -on the AIC. However, fitting the DFOP model with constant variance and -using default control parameters results in an error, signalling that -the maximum number of 50 iterations was reached, potentially indicating -overparameterisation. Nevertheless, the algorithm converges when the -two-component error model is used in combination with the DFOP model. -This can be explained by the fact that the smaller residues observed at -later sampling times get more weight when using the two-component error -model which will counteract the tendency of the algorithm to try -parameter combinations unsuitable for fitting these data.</p> -<div class="sourceCode" id="cb9"><pre class="downlit sourceCode r"> -<code class="sourceCode R"><span><span class="kw"><a href="https://rdrr.io/r/base/library.html" class="external-link">library</a></span><span class="op">(</span><span class="va"><a href="https://svn.r-project.org/R-packages/trunk/nlme/" class="external-link">nlme</a></span><span class="op">)</span></span> -<span><span class="va">f_parent_nlme_sfo_const</span> <span class="op"><-</span> <span class="fu"><a href="https://rdrr.io/pkg/nlme/man/nlme.html" class="external-link">nlme</a></span><span class="op">(</span><span class="va">f_parent_mkin_const</span><span class="op">[</span><span class="st">"SFO"</span>, <span class="op">]</span><span class="op">)</span></span> -<span><span class="co"># f_parent_nlme_dfop_const <- nlme(f_parent_mkin_const["DFOP", ])</span></span> -<span><span class="va">f_parent_nlme_sfo_tc</span> <span class="op"><-</span> <span class="fu"><a href="https://rdrr.io/pkg/nlme/man/nlme.html" class="external-link">nlme</a></span><span class="op">(</span><span class="va">f_parent_mkin_tc</span><span class="op">[</span><span class="st">"SFO"</span>, <span class="op">]</span><span class="op">)</span></span> -<span><span class="va">f_parent_nlme_dfop_tc</span> <span class="op"><-</span> <span class="fu"><a href="https://rdrr.io/pkg/nlme/man/nlme.html" class="external-link">nlme</a></span><span class="op">(</span><span class="va">f_parent_mkin_tc</span><span class="op">[</span><span class="st">"DFOP"</span>, <span class="op">]</span><span class="op">)</span></span></code></pre></div> -<p>Note that a certain degree of overparameterisation is also indicated -by a warning obtained when fitting DFOP with the two-component error -model (‘false convergence’ in the ‘LME step’ in iteration 3). However, -as this warning does not occur in later iterations, and specifically not -in the last of the 5 iterations, we can ignore this warning.</p> -<p>The model comparison function of the nlme package can directly be -applied to these fits showing a much lower AIC for the DFOP model fitted -with the two-component error model. Also, the likelihood ratio test -indicates that this difference is significant as the p-value is below -0.0001.</p> -<div class="sourceCode" id="cb10"><pre class="downlit sourceCode r"> -<code class="sourceCode R"><span><span class="fu"><a href="https://rdrr.io/r/stats/anova.html" class="external-link">anova</a></span><span class="op">(</span></span> -<span> <span class="va">f_parent_nlme_sfo_const</span>, <span class="va">f_parent_nlme_sfo_tc</span>, <span class="va">f_parent_nlme_dfop_tc</span></span> -<span><span class="op">)</span></span></code></pre></div> -<pre><code> Model df AIC BIC logLik Test L.Ratio p-value -f_parent_nlme_sfo_const 1 5 796.60 811.82 -393.30 -f_parent_nlme_sfo_tc 2 6 798.60 816.86 -393.30 1 vs 2 0.00 0.998 -f_parent_nlme_dfop_tc 3 10 671.91 702.34 -325.96 2 vs 3 134.69 <.0001</code></pre> -<p>In addition to these fits, attempts were also made to include -correlations between random effects by using the log Cholesky -parameterisation of the matrix specifying them. The code used for these -attempts can be made visible below.</p> -<div class="sourceCode" id="cb12"><pre class="downlit sourceCode r"> -<code class="sourceCode R"><span><span class="va">f_parent_nlme_sfo_const_logchol</span> <span class="op"><-</span> <span class="fu"><a href="https://rdrr.io/pkg/nlme/man/nlme.html" class="external-link">nlme</a></span><span class="op">(</span><span class="va">f_parent_mkin_const</span><span class="op">[</span><span class="st">"SFO"</span>, <span class="op">]</span>,</span> -<span> random <span class="op">=</span> <span class="fu">nlme</span><span class="fu">::</span><span class="fu"><a href="https://rdrr.io/pkg/nlme/man/pdLogChol.html" class="external-link">pdLogChol</a></span><span class="op">(</span><span class="fu"><a href="https://rdrr.io/r/base/list.html" class="external-link">list</a></span><span class="op">(</span><span class="va">DMTA_0</span> <span class="op">~</span> <span class="fl">1</span>, <span class="va">log_k_DMTA</span> <span class="op">~</span> <span class="fl">1</span><span class="op">)</span><span class="op">)</span><span class="op">)</span></span> -<span><span class="fu"><a href="https://rdrr.io/r/stats/anova.html" class="external-link">anova</a></span><span class="op">(</span><span class="va">f_parent_nlme_sfo_const</span>, <span class="va">f_parent_nlme_sfo_const_logchol</span><span class="op">)</span></span> -<span><span class="va">f_parent_nlme_sfo_tc_logchol</span> <span class="op"><-</span> <span class="fu"><a href="https://rdrr.io/pkg/nlme/man/nlme.html" class="external-link">nlme</a></span><span class="op">(</span><span class="va">f_parent_mkin_tc</span><span class="op">[</span><span class="st">"SFO"</span>, <span class="op">]</span>,</span> -<span> random <span class="op">=</span> <span class="fu">nlme</span><span class="fu">::</span><span class="fu"><a href="https://rdrr.io/pkg/nlme/man/pdLogChol.html" class="external-link">pdLogChol</a></span><span class="op">(</span><span class="fu"><a href="https://rdrr.io/r/base/list.html" class="external-link">list</a></span><span class="op">(</span><span class="va">DMTA_0</span> <span class="op">~</span> <span class="fl">1</span>, <span class="va">log_k_DMTA</span> <span class="op">~</span> <span class="fl">1</span><span class="op">)</span><span class="op">)</span><span class="op">)</span></span> -<span><span class="fu"><a href="https://rdrr.io/r/stats/anova.html" class="external-link">anova</a></span><span class="op">(</span><span class="va">f_parent_nlme_sfo_tc</span>, <span class="va">f_parent_nlme_sfo_tc_logchol</span><span class="op">)</span></span> -<span><span class="va">f_parent_nlme_dfop_tc_logchol</span> <span class="op"><-</span> <span class="fu"><a href="https://rdrr.io/pkg/nlme/man/nlme.html" class="external-link">nlme</a></span><span class="op">(</span><span class="va">f_parent_mkin_const</span><span class="op">[</span><span class="st">"DFOP"</span>, <span class="op">]</span>,</span> -<span> random <span class="op">=</span> <span class="fu">nlme</span><span class="fu">::</span><span class="fu"><a href="https://rdrr.io/pkg/nlme/man/pdLogChol.html" class="external-link">pdLogChol</a></span><span class="op">(</span><span class="fu"><a href="https://rdrr.io/r/base/list.html" class="external-link">list</a></span><span class="op">(</span><span class="va">DMTA_0</span> <span class="op">~</span> <span class="fl">1</span>, <span class="va">log_k1</span> <span class="op">~</span> <span class="fl">1</span>, <span class="va">log_k2</span> <span class="op">~</span> <span class="fl">1</span>, <span class="va">g_qlogis</span> <span class="op">~</span> <span class="fl">1</span><span class="op">)</span><span class="op">)</span><span class="op">)</span></span> -<span><span class="fu"><a href="https://rdrr.io/r/stats/anova.html" class="external-link">anova</a></span><span class="op">(</span><span class="va">f_parent_nlme_dfop_tc</span>, <span class="va">f_parent_nlme_dfop_tc_logchol</span><span class="op">)</span></span></code></pre></div> -<p>While the SFO variants converge fast, the additional parameters -introduced by this lead to convergence warnings for the DFOP model. The -model comparison clearly show that adding correlations between random -effects does not improve the fits.</p> -<p>The selected model (DFOP with two-component error) fitted to the data -assuming no correlations between random effects is shown below.</p> -<div class="sourceCode" id="cb13"><pre class="downlit sourceCode r"> -<code class="sourceCode R"><span><span class="fu"><a href="https://rdrr.io/r/base/plot.html" class="external-link">plot</a></span><span class="op">(</span><span class="va">f_parent_nlme_dfop_tc</span><span class="op">)</span></span></code></pre></div> -<p><img src="dimethenamid_2018_files/figure-html/plot_parent_nlme-1.png" width="700"></p> -</div> -<div class="section level4"> -<h4 id="saemix">saemix<a class="anchor" aria-label="anchor" href="#saemix"></a> -</h4> -<p>The saemix package provided the first Open Source implementation of -the Stochastic Approximation to the Expectation Maximisation (SAEM) -algorithm. SAEM fits of degradation models can be conveniently performed -using an interface to the saemix package available in current -development versions of the mkin package.</p> -<p>The corresponding SAEM fits of the four combinations of degradation -and error models are fitted below. As there is no convergence criterion -implemented in the saemix package, the convergence plots need to be -manually checked for every fit. We define control settings that work -well for all the parent data fits shown in this vignette.</p> -<div class="sourceCode" id="cb14"><pre class="downlit sourceCode r"> -<code class="sourceCode R"><span><span class="kw"><a href="https://rdrr.io/r/base/library.html" class="external-link">library</a></span><span class="op">(</span><span class="va">saemix</span><span class="op">)</span></span> -<span><span class="va">saemix_control</span> <span class="op"><-</span> <span class="fu"><a href="https://rdrr.io/pkg/saemix/man/saemixControl.html" class="external-link">saemixControl</a></span><span class="op">(</span>nbiter.saemix <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/c.html" class="external-link">c</a></span><span class="op">(</span><span class="fl">800</span>, <span class="fl">300</span><span class="op">)</span>, nb.chains <span class="op">=</span> <span class="fl">15</span>,</span> -<span> print <span class="op">=</span> <span class="cn">FALSE</span>, save <span class="op">=</span> <span class="cn">FALSE</span>, save.graphs <span class="op">=</span> <span class="cn">FALSE</span>, displayProgress <span class="op">=</span> <span class="cn">FALSE</span><span class="op">)</span></span> -<span><span class="va">saemix_control_moreiter</span> <span class="op"><-</span> <span class="fu"><a href="https://rdrr.io/pkg/saemix/man/saemixControl.html" class="external-link">saemixControl</a></span><span class="op">(</span>nbiter.saemix <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/c.html" class="external-link">c</a></span><span class="op">(</span><span class="fl">1600</span>, <span class="fl">300</span><span class="op">)</span>, nb.chains <span class="op">=</span> <span class="fl">15</span>,</span> -<span> print <span class="op">=</span> <span class="cn">FALSE</span>, save <span class="op">=</span> <span class="cn">FALSE</span>, save.graphs <span class="op">=</span> <span class="cn">FALSE</span>, displayProgress <span class="op">=</span> <span class="cn">FALSE</span><span class="op">)</span></span> -<span><span class="va">saemix_control_10k</span> <span class="op"><-</span> <span class="fu"><a href="https://rdrr.io/pkg/saemix/man/saemixControl.html" class="external-link">saemixControl</a></span><span class="op">(</span>nbiter.saemix <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/c.html" class="external-link">c</a></span><span class="op">(</span><span class="fl">10000</span>, <span class="fl">300</span><span class="op">)</span>, nb.chains <span class="op">=</span> <span class="fl">15</span>,</span> -<span> print <span class="op">=</span> <span class="cn">FALSE</span>, save <span class="op">=</span> <span class="cn">FALSE</span>, save.graphs <span class="op">=</span> <span class="cn">FALSE</span>, displayProgress <span class="op">=</span> <span class="cn">FALSE</span><span class="op">)</span></span></code></pre></div> -<p>The convergence plot for the SFO model using constant variance is -shown below.</p> -<div class="sourceCode" id="cb15"><pre class="downlit sourceCode r"> -<code class="sourceCode R"><span><span class="va">f_parent_saemix_sfo_const</span> <span class="op"><-</span> <span class="fu">mkin</span><span class="fu">::</span><span class="fu"><a href="../../reference/saem.html">saem</a></span><span class="op">(</span><span class="va">f_parent_mkin_const</span><span class="op">[</span><span class="st">"SFO"</span>, <span class="op">]</span>, quiet <span class="op">=</span> <span class="cn">TRUE</span>,</span> -<span> control <span class="op">=</span> <span class="va">saemix_control</span>, transformations <span class="op">=</span> <span class="st">"saemix"</span><span class="op">)</span></span> -<span><span class="fu"><a href="https://rdrr.io/r/base/plot.html" class="external-link">plot</a></span><span class="op">(</span><span class="va">f_parent_saemix_sfo_const</span><span class="op">$</span><span class="va">so</span>, plot.type <span class="op">=</span> <span class="st">"convergence"</span><span class="op">)</span></span></code></pre></div> -<p><img src="dimethenamid_2018_files/figure-html/f_parent_saemix_sfo_const-1.png" width="700"></p> -<p>Obviously the selected number of iterations is sufficient to reach -convergence. This can also be said for the SFO fit using the -two-component error model.</p> -<div class="sourceCode" id="cb16"><pre class="downlit sourceCode r"> -<code class="sourceCode R"><span><span class="va">f_parent_saemix_sfo_tc</span> <span class="op"><-</span> <span class="fu">mkin</span><span class="fu">::</span><span class="fu"><a href="../../reference/saem.html">saem</a></span><span class="op">(</span><span class="va">f_parent_mkin_tc</span><span class="op">[</span><span class="st">"SFO"</span>, <span class="op">]</span>, quiet <span class="op">=</span> <span class="cn">TRUE</span>,</span> -<span> control <span class="op">=</span> <span class="va">saemix_control</span>, transformations <span class="op">=</span> <span class="st">"saemix"</span><span class="op">)</span></span> -<span><span class="fu"><a href="https://rdrr.io/r/base/plot.html" class="external-link">plot</a></span><span class="op">(</span><span class="va">f_parent_saemix_sfo_tc</span><span class="op">$</span><span class="va">so</span>, plot.type <span class="op">=</span> <span class="st">"convergence"</span><span class="op">)</span></span></code></pre></div> -<p><img src="dimethenamid_2018_files/figure-html/f_parent_saemix_sfo_tc-1.png" width="700"></p> -<p>When fitting the DFOP model with constant variance (see below), -parameter convergence is not as unambiguous.</p> -<div class="sourceCode" id="cb17"><pre class="downlit sourceCode r"> -<code class="sourceCode R"><span><span class="va">f_parent_saemix_dfop_const</span> <span class="op"><-</span> <span class="fu">mkin</span><span class="fu">::</span><span class="fu"><a href="../../reference/saem.html">saem</a></span><span class="op">(</span><span class="va">f_parent_mkin_const</span><span class="op">[</span><span class="st">"DFOP"</span>, <span class="op">]</span>, quiet <span class="op">=</span> <span class="cn">TRUE</span>,</span> -<span> control <span class="op">=</span> <span class="va">saemix_control</span>, transformations <span class="op">=</span> <span class="st">"saemix"</span><span class="op">)</span></span> -<span><span class="fu"><a href="https://rdrr.io/r/base/plot.html" class="external-link">plot</a></span><span class="op">(</span><span class="va">f_parent_saemix_dfop_const</span><span class="op">$</span><span class="va">so</span>, plot.type <span class="op">=</span> <span class="st">"convergence"</span><span class="op">)</span></span></code></pre></div> -<p><img src="dimethenamid_2018_files/figure-html/f_parent_saemix_dfop_const-1.png" width="700"></p> -<div class="sourceCode" id="cb18"><pre class="downlit sourceCode r"> -<code class="sourceCode R"><span><span class="fu"><a href="https://rdrr.io/r/base/print.html" class="external-link">print</a></span><span class="op">(</span><span class="va">f_parent_saemix_dfop_const</span><span class="op">)</span></span></code></pre></div> -<pre><code>Kinetic nonlinear mixed-effects model fit by SAEM -Structural model: -d_DMTA/dt = - ((k1 * g * exp(-k1 * time) + k2 * (1 - g) * exp(-k2 * - time)) / (g * exp(-k1 * time) + (1 - g) * exp(-k2 * time))) - * DMTA - -Data: -155 observations of 1 variable(s) grouped in 6 datasets - -Likelihood computed by importance sampling - AIC BIC logLik - 706 704 -344 - -Fitted parameters: - estimate lower upper -DMTA_0 97.99583 96.50079 99.4909 -k1 0.06377 0.03432 0.0932 -k2 0.00848 0.00444 0.0125 -g 0.95701 0.91313 1.0009 -a.1 1.82141 1.65122 1.9916 -SD.DMTA_0 1.64787 0.45772 2.8380 -SD.k1 0.57439 0.24731 0.9015 -SD.k2 0.03296 -2.50195 2.5679 -SD.g 1.10266 0.32369 1.8816</code></pre> -<p>While the other parameters converge to credible values, the variance -of k2 (<code>omega2.k2</code>) converges to a very small value. The -printout of the <code>saem.mmkin</code> model shows that the estimated -standard deviation of k2 across the population of soils -(<code>SD.k2</code>) is ill-defined, indicating overparameterisation of -this model.</p> -<p>When the DFOP model is fitted with the two-component error model, we -also observe that the estimated variance of k2 becomes very small, while -being ill-defined, as illustrated by the excessive confidence interval -of <code>SD.k2</code>.</p> -<div class="sourceCode" id="cb20"><pre class="downlit sourceCode r"> -<code class="sourceCode R"><span><span class="va">f_parent_saemix_dfop_tc</span> <span class="op"><-</span> <span class="fu">mkin</span><span class="fu">::</span><span class="fu"><a href="../../reference/saem.html">saem</a></span><span class="op">(</span><span class="va">f_parent_mkin_tc</span><span class="op">[</span><span class="st">"DFOP"</span>, <span class="op">]</span>, quiet <span class="op">=</span> <span class="cn">TRUE</span>,</span> -<span> control <span class="op">=</span> <span class="va">saemix_control</span>, transformations <span class="op">=</span> <span class="st">"saemix"</span><span class="op">)</span></span> -<span><span class="va">f_parent_saemix_dfop_tc_moreiter</span> <span class="op"><-</span> <span class="fu">mkin</span><span class="fu">::</span><span class="fu"><a href="../../reference/saem.html">saem</a></span><span class="op">(</span><span class="va">f_parent_mkin_tc</span><span class="op">[</span><span class="st">"DFOP"</span>, <span class="op">]</span>, quiet <span class="op">=</span> <span class="cn">TRUE</span>,</span> -<span> control <span class="op">=</span> <span class="va">saemix_control_moreiter</span>, transformations <span class="op">=</span> <span class="st">"saemix"</span><span class="op">)</span></span> -<span><span class="fu"><a href="https://rdrr.io/r/base/plot.html" class="external-link">plot</a></span><span class="op">(</span><span class="va">f_parent_saemix_dfop_tc</span><span class="op">$</span><span class="va">so</span>, plot.type <span class="op">=</span> <span class="st">"convergence"</span><span class="op">)</span></span></code></pre></div> -<p><img src="dimethenamid_2018_files/figure-html/f_parent_saemix_dfop_tc-1.png" width="700"></p> -<div class="sourceCode" id="cb21"><pre class="downlit sourceCode r"> -<code class="sourceCode R"><span><span class="fu"><a href="https://rdrr.io/r/base/print.html" class="external-link">print</a></span><span class="op">(</span><span class="va">f_parent_saemix_dfop_tc</span><span class="op">)</span></span></code></pre></div> -<pre><code>Kinetic nonlinear mixed-effects model fit by SAEM -Structural model: -d_DMTA/dt = - ((k1 * g * exp(-k1 * time) + k2 * (1 - g) * exp(-k2 * - time)) / (g * exp(-k1 * time) + (1 - g) * exp(-k2 * time))) - * DMTA - -Data: -155 observations of 1 variable(s) grouped in 6 datasets - -Likelihood computed by importance sampling - AIC BIC logLik - 666 664 -323 - -Fitted parameters: - estimate lower upper -DMTA_0 98.27617 96.3088 100.2436 -k1 0.06437 0.0337 0.0950 -k2 0.00880 0.0063 0.0113 -g 0.95249 0.9100 0.9949 -a.1 1.06161 0.8625 1.2607 -b.1 0.02967 0.0226 0.0367 -SD.DMTA_0 2.06075 0.4187 3.7028 -SD.k1 0.59357 0.2561 0.9310 -SD.k2 0.00292 -10.2960 10.3019 -SD.g 1.05725 0.3808 1.7337</code></pre> -<p>Doubling the number of iterations in the first phase of the algorithm -leads to a slightly lower likelihood, and therefore to slightly higher -AIC and BIC values. With even more iterations, the algorithm stops with -an error message. This is related to the variance of k2 approximating -zero and has been submitted as a <a href="https://github.com/saemixdevelopment/saemixextension/issues/29" class="external-link">bug -to the saemix package</a>, as the algorithm does not converge in this -case.</p> -<p>An alternative way to fit DFOP in combination with the two-component -error model is to use the model formulation with transformed parameters -as used per default in mkin. When using this option, convergence is -slower, but eventually the algorithm stops as well with the same error -message.</p> -<p>The four combinations (SFO/const, SFO/tc, DFOP/const and DFOP/tc) and -the version with increased iterations can be compared using the model -comparison function of the saemix package:</p> -<div class="sourceCode" id="cb23"><pre class="downlit sourceCode r"> -<code class="sourceCode R"><span><span class="va">AIC_parent_saemix</span> <span class="op"><-</span> <span class="fu">saemix</span><span class="fu">::</span><span class="fu"><a href="https://rdrr.io/pkg/saemix/man/compare.saemix.html" class="external-link">compare.saemix</a></span><span class="op">(</span></span> -<span> <span class="va">f_parent_saemix_sfo_const</span><span class="op">$</span><span class="va">so</span>,</span> -<span> <span class="va">f_parent_saemix_sfo_tc</span><span class="op">$</span><span class="va">so</span>,</span> -<span> <span class="va">f_parent_saemix_dfop_const</span><span class="op">$</span><span class="va">so</span>,</span> -<span> <span class="va">f_parent_saemix_dfop_tc</span><span class="op">$</span><span class="va">so</span>,</span> -<span> <span class="va">f_parent_saemix_dfop_tc_moreiter</span><span class="op">$</span><span class="va">so</span><span class="op">)</span></span></code></pre></div> -<pre><code>Likelihoods calculated by importance sampling</code></pre> -<div class="sourceCode" id="cb25"><pre class="downlit sourceCode r"> -<code class="sourceCode R"><span><span class="fu"><a href="https://rdrr.io/r/base/colnames.html" class="external-link">rownames</a></span><span class="op">(</span><span class="va">AIC_parent_saemix</span><span class="op">)</span> <span class="op"><-</span> <span class="fu"><a href="https://rdrr.io/r/base/c.html" class="external-link">c</a></span><span class="op">(</span></span> -<span> <span class="st">"SFO const"</span>, <span class="st">"SFO tc"</span>, <span class="st">"DFOP const"</span>, <span class="st">"DFOP tc"</span>, <span class="st">"DFOP tc more iterations"</span><span class="op">)</span></span> -<span><span class="fu"><a href="https://rdrr.io/r/base/print.html" class="external-link">print</a></span><span class="op">(</span><span class="va">AIC_parent_saemix</span><span class="op">)</span></span></code></pre></div> -<pre><code> AIC BIC -SFO const 796.38 795.34 -SFO tc 798.38 797.13 -DFOP const 705.75 703.88 -DFOP tc 665.65 663.57 -DFOP tc more iterations 665.88 663.80</code></pre> -<p>In order to check the influence of the likelihood calculation -algorithms implemented in saemix, the likelihood from Gaussian -quadrature is added to the best fit, and the AIC values obtained from -the three methods are compared.</p> -<div class="sourceCode" id="cb27"><pre class="downlit sourceCode r"> -<code class="sourceCode R"><span><span class="va">f_parent_saemix_dfop_tc</span><span class="op">$</span><span class="va">so</span> <span class="op"><-</span></span> -<span> <span class="fu">saemix</span><span class="fu">::</span><span class="fu"><a href="https://rdrr.io/pkg/saemix/man/llgq.saemix.html" class="external-link">llgq.saemix</a></span><span class="op">(</span><span class="va">f_parent_saemix_dfop_tc</span><span class="op">$</span><span class="va">so</span><span class="op">)</span></span> -<span><span class="va">AIC_parent_saemix_methods</span> <span class="op"><-</span> <span class="fu"><a href="https://rdrr.io/r/base/c.html" class="external-link">c</a></span><span class="op">(</span></span> -<span> is <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/stats/AIC.html" class="external-link">AIC</a></span><span class="op">(</span><span class="va">f_parent_saemix_dfop_tc</span><span class="op">$</span><span class="va">so</span>, method <span class="op">=</span> <span class="st">"is"</span><span class="op">)</span>,</span> -<span> gq <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/stats/AIC.html" class="external-link">AIC</a></span><span class="op">(</span><span class="va">f_parent_saemix_dfop_tc</span><span class="op">$</span><span class="va">so</span>, method <span class="op">=</span> <span class="st">"gq"</span><span class="op">)</span>,</span> -<span> lin <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/stats/AIC.html" class="external-link">AIC</a></span><span class="op">(</span><span class="va">f_parent_saemix_dfop_tc</span><span class="op">$</span><span class="va">so</span>, method <span class="op">=</span> <span class="st">"lin"</span><span class="op">)</span></span> -<span><span class="op">)</span></span> -<span><span class="fu"><a href="https://rdrr.io/r/base/print.html" class="external-link">print</a></span><span class="op">(</span><span class="va">AIC_parent_saemix_methods</span><span class="op">)</span></span></code></pre></div> -<pre><code> is gq lin -665.65 665.68 665.11 </code></pre> -<p>The AIC values based on importance sampling and Gaussian quadrature -are very similar. Using linearisation is known to be less accurate, but -still gives a similar value.</p> -<p>In order to illustrate that the comparison of the three method -depends on the degree of convergence obtained in the fit, the same -comparison is shown below for the fit using the defaults for the number -of iterations and the number of MCMC chains.</p> -<p>When using OpenBlas for linear algebra, there is a large difference -in the values obtained with Gaussian quadrature, so the larger number of -iterations makes a lot of difference. When using the LAPACK version -coming with Debian Bullseye, the AIC based on Gaussian quadrature is -almost the same as the one obtained with the other methods, also when -using defaults for the fit.</p> -<div class="sourceCode" id="cb29"><pre class="downlit sourceCode r"> -<code class="sourceCode R"><span><span class="va">f_parent_saemix_dfop_tc_defaults</span> <span class="op"><-</span> <span class="fu">mkin</span><span class="fu">::</span><span class="fu"><a href="../../reference/saem.html">saem</a></span><span class="op">(</span><span class="va">f_parent_mkin_tc</span><span class="op">[</span><span class="st">"DFOP"</span>, <span class="op">]</span><span class="op">)</span></span> -<span><span class="va">f_parent_saemix_dfop_tc_defaults</span><span class="op">$</span><span class="va">so</span> <span class="op"><-</span></span> -<span> <span class="fu">saemix</span><span class="fu">::</span><span class="fu"><a href="https://rdrr.io/pkg/saemix/man/llgq.saemix.html" class="external-link">llgq.saemix</a></span><span class="op">(</span><span class="va">f_parent_saemix_dfop_tc_defaults</span><span class="op">$</span><span class="va">so</span><span class="op">)</span></span> -<span><span class="va">AIC_parent_saemix_methods_defaults</span> <span class="op"><-</span> <span class="fu"><a href="https://rdrr.io/r/base/c.html" class="external-link">c</a></span><span class="op">(</span></span> -<span> is <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/stats/AIC.html" class="external-link">AIC</a></span><span class="op">(</span><span class="va">f_parent_saemix_dfop_tc_defaults</span><span class="op">$</span><span class="va">so</span>, method <span class="op">=</span> <span class="st">"is"</span><span class="op">)</span>,</span> -<span> gq <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/stats/AIC.html" class="external-link">AIC</a></span><span class="op">(</span><span class="va">f_parent_saemix_dfop_tc_defaults</span><span class="op">$</span><span class="va">so</span>, method <span class="op">=</span> <span class="st">"gq"</span><span class="op">)</span>,</span> -<span> lin <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/stats/AIC.html" class="external-link">AIC</a></span><span class="op">(</span><span class="va">f_parent_saemix_dfop_tc_defaults</span><span class="op">$</span><span class="va">so</span>, method <span class="op">=</span> <span class="st">"lin"</span><span class="op">)</span></span> -<span><span class="op">)</span></span> -<span><span class="fu"><a href="https://rdrr.io/r/base/print.html" class="external-link">print</a></span><span class="op">(</span><span class="va">AIC_parent_saemix_methods_defaults</span><span class="op">)</span></span></code></pre></div> -<pre><code> is gq lin -669.77 669.36 670.95 </code></pre> -</div> -</div> -<div class="section level3"> -<h3 id="comparison">Comparison<a class="anchor" aria-label="anchor" href="#comparison"></a> -</h3> -<p>The following table gives the AIC values obtained with both backend -packages using the same control parameters (800 iterations burn-in, 300 -iterations second phase, 15 chains).</p> -<div class="sourceCode" id="cb31"><pre class="downlit sourceCode r"> -<code class="sourceCode R"><span><span class="va">AIC_all</span> <span class="op"><-</span> <span class="fu"><a href="https://rdrr.io/r/base/data.frame.html" class="external-link">data.frame</a></span><span class="op">(</span></span> -<span> check.names <span class="op">=</span> <span class="cn">FALSE</span>,</span> -<span> <span class="st">"Degradation model"</span> <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/c.html" class="external-link">c</a></span><span class="op">(</span><span class="st">"SFO"</span>, <span class="st">"SFO"</span>, <span class="st">"DFOP"</span>, <span class="st">"DFOP"</span><span class="op">)</span>,</span> -<span> <span class="st">"Error model"</span> <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/c.html" class="external-link">c</a></span><span class="op">(</span><span class="st">"const"</span>, <span class="st">"tc"</span>, <span class="st">"const"</span>, <span class="st">"tc"</span><span class="op">)</span>,</span> -<span> nlme <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/c.html" class="external-link">c</a></span><span class="op">(</span><span class="fu"><a href="https://rdrr.io/r/stats/AIC.html" class="external-link">AIC</a></span><span class="op">(</span><span class="va">f_parent_nlme_sfo_const</span><span class="op">)</span>, <span class="fu"><a href="https://rdrr.io/r/stats/AIC.html" class="external-link">AIC</a></span><span class="op">(</span><span class="va">f_parent_nlme_sfo_tc</span><span class="op">)</span>, <span class="cn">NA</span>, <span class="fu"><a href="https://rdrr.io/r/stats/AIC.html" class="external-link">AIC</a></span><span class="op">(</span><span class="va">f_parent_nlme_dfop_tc</span><span class="op">)</span><span class="op">)</span>,</span> -<span> saemix_lin <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/lapply.html" class="external-link">sapply</a></span><span class="op">(</span><span class="fu"><a href="https://rdrr.io/r/base/list.html" class="external-link">list</a></span><span class="op">(</span><span class="va">f_parent_saemix_sfo_const</span><span class="op">$</span><span class="va">so</span>, <span class="va">f_parent_saemix_sfo_tc</span><span class="op">$</span><span class="va">so</span>,</span> -<span> <span class="va">f_parent_saemix_dfop_const</span><span class="op">$</span><span class="va">so</span>, <span class="va">f_parent_saemix_dfop_tc</span><span class="op">$</span><span class="va">so</span><span class="op">)</span>, <span class="va">AIC</span>, method <span class="op">=</span> <span class="st">"lin"</span><span class="op">)</span>,</span> -<span> saemix_is <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/lapply.html" class="external-link">sapply</a></span><span class="op">(</span><span class="fu"><a href="https://rdrr.io/r/base/list.html" class="external-link">list</a></span><span class="op">(</span><span class="va">f_parent_saemix_sfo_const</span><span class="op">$</span><span class="va">so</span>, <span class="va">f_parent_saemix_sfo_tc</span><span class="op">$</span><span class="va">so</span>,</span> -<span> <span class="va">f_parent_saemix_dfop_const</span><span class="op">$</span><span class="va">so</span>, <span class="va">f_parent_saemix_dfop_tc</span><span class="op">$</span><span class="va">so</span><span class="op">)</span>, <span class="va">AIC</span>, method <span class="op">=</span> <span class="st">"is"</span><span class="op">)</span></span> -<span><span class="op">)</span></span> -<span><span class="fu"><a href="https://rdrr.io/pkg/knitr/man/kable.html" class="external-link">kable</a></span><span class="op">(</span><span class="va">AIC_all</span><span class="op">)</span></span></code></pre></div> -<table class="table"> -<thead><tr class="header"> -<th align="left">Degradation model</th> -<th align="left">Error model</th> -<th align="right">nlme</th> -<th align="right">saemix_lin</th> -<th align="right">saemix_is</th> -</tr></thead> -<tbody> -<tr class="odd"> -<td align="left">SFO</td> -<td align="left">const</td> -<td align="right">796.60</td> -<td align="right">796.60</td> -<td align="right">796.38</td> -</tr> -<tr class="even"> -<td align="left">SFO</td> -<td align="left">tc</td> -<td align="right">798.60</td> -<td align="right">798.60</td> -<td align="right">798.38</td> -</tr> -<tr class="odd"> -<td align="left">DFOP</td> -<td align="left">const</td> -<td align="right">NA</td> -<td align="right">709.26</td> -<td align="right">705.75</td> -</tr> -<tr class="even"> -<td align="left">DFOP</td> -<td align="left">tc</td> -<td align="right">671.91</td> -<td align="right">665.11</td> -<td align="right">665.65</td> -</tr> -</tbody> -</table> -</div> -</div> -<div class="section level2"> -<h2 id="conclusion">Conclusion<a class="anchor" aria-label="anchor" href="#conclusion"></a> -</h2> -<p>A more detailed analysis of the dimethenamid dataset confirmed that -the DFOP model provides the most appropriate description of the decline -of the parent compound in these data. On the other hand, closer -inspection of the results revealed that the variability of the k2 -parameter across the population of soils is ill-defined. This coincides -with the observation that this parameter cannot robustly be quantified -for some of the soils.</p> -<p>Regarding the regulatory use of these data, it is claimed that an -improved characterisation of the mean parameter values across the -population is obtained using the nonlinear mixed-effects models -presented here. However, attempts to quantify the variability of the -slower rate constant of the biphasic decline of dimethenamid indicate -that the data are not sufficient to characterise this variability to a -satisfactory precision.</p> -</div> -<div class="section level2"> -<h2 id="session-info">Session Info<a class="anchor" aria-label="anchor" href="#session-info"></a> -</h2> -<div class="sourceCode" id="cb32"><pre class="downlit sourceCode r"> -<code class="sourceCode R"><span><span class="fu"><a href="https://rdrr.io/r/utils/sessionInfo.html" class="external-link">sessionInfo</a></span><span class="op">(</span><span class="op">)</span></span></code></pre></div> -<pre><code>R version 4.2.3 (2023-03-15) -Platform: x86_64-pc-linux-gnu (64-bit) -Running under: Debian GNU/Linux 12 (bookworm) - -Matrix products: default -BLAS: /usr/lib/x86_64-linux-gnu/openblas-serial/libblas.so.3 -LAPACK: /usr/lib/x86_64-linux-gnu/openblas-serial/libopenblas-r0.3.21.so - -locale: - [1] LC_CTYPE=de_DE.UTF-8 LC_NUMERIC=C - [3] LC_TIME=C LC_COLLATE=de_DE.UTF-8 - [5] LC_MONETARY=de_DE.UTF-8 LC_MESSAGES=de_DE.UTF-8 - [7] LC_PAPER=de_DE.UTF-8 LC_NAME=C - [9] LC_ADDRESS=C LC_TELEPHONE=C -[11] LC_MEASUREMENT=de_DE.UTF-8 LC_IDENTIFICATION=C - -attached base packages: -[1] stats graphics grDevices utils datasets methods base - -other attached packages: -[1] saemix_3.2 npde_3.3 nlme_3.1-162 mkin_1.2.3 knitr_1.42 - -loaded via a namespace (and not attached): - [1] highr_0.10 pillar_1.9.0 bslib_0.4.2 compiler_4.2.3 - [5] jquerylib_0.1.4 tools_4.2.3 mclust_6.0.0 digest_0.6.31 - [9] tibble_3.2.1 jsonlite_1.8.4 evaluate_0.20 memoise_2.0.1 -[13] lifecycle_1.0.3 gtable_0.3.3 lattice_0.21-8 pkgconfig_2.0.3 -[17] rlang_1.1.0 DBI_1.1.3 cli_3.6.1 yaml_2.3.7 -[21] parallel_4.2.3 pkgdown_2.0.7 xfun_0.38 fastmap_1.1.1 -[25] gridExtra_2.3 dplyr_1.1.1 stringr_1.5.0 generics_0.1.3 -[29] desc_1.4.2 fs_1.6.1 vctrs_0.6.1 sass_0.4.5 -[33] systemfonts_1.0.4 tidyselect_1.2.0 rprojroot_2.0.3 lmtest_0.9-40 -[37] grid_4.2.3 glue_1.6.2 R6_2.5.1 textshaping_0.3.6 -[41] fansi_1.0.4 rmarkdown_2.21 purrr_1.0.1 ggplot2_3.4.2 -[45] magrittr_2.0.3 codetools_0.2-19 scales_1.2.1 htmltools_0.5.5 -[49] colorspace_2.1-0 ragg_1.2.5 utf8_1.2.3 stringi_1.7.12 -[53] munsell_0.5.0 cachem_1.0.7 zoo_1.8-12 </code></pre> -</div> -<div class="section level2"> -<h2 id="references">References<a class="anchor" aria-label="anchor" href="#references"></a> -</h2> -<!-- vim: set foldmethod=syntax: --> -<div id="refs" class="references csl-bib-body hanging-indent"> -<div id="ref-efsa_2018_dimethenamid" class="csl-entry"> -EFSA. 2018. <span>“Peer Review of the Pesticide Risk Assessment of the -Active Substance Dimethenamid-p.”</span> <em>EFSA Journal</em> 16: 5211. -</div> -<div id="ref-ranke2021" class="csl-entry"> -Ranke, Johannes, Janina Wöltjen, Jana Schmidt, and Emmanuelle Comets. -2021. <span>“Taking Kinetic Evaluations of Degradation Data to the Next -Level with Nonlinear Mixed-Effects Models.”</span> <em>Environments</em> -8 (8). <a href="https://doi.org/10.3390/environments8080071" class="external-link">https://doi.org/10.3390/environments8080071</a>. -</div> -<div id="ref-dimethenamid_rar_2018_b8" class="csl-entry"> -Rapporteur Member State Germany, Co-Rapporteur Member State Bulgaria. -2018. <span>“<span class="nocase">Renewal Assessment Report -Dimethenamid-P Volume 3 - B.8 Environmental fate and behaviour, Rev. 2 - -November 2017</span>.”</span> <a href="https://open.efsa.europa.eu/study-inventory/EFSA-Q-2014-00716" class="external-link">https://open.efsa.europa.eu/study-inventory/EFSA-Q-2014-00716</a>. -</div> -</div> -</div> - </div> - - <div class="col-md-3 hidden-xs hidden-sm" id="pkgdown-sidebar"> - - <nav id="toc" data-toggle="toc"><h2 data-toc-skip>Contents</h2> - </nav> -</div> - -</div> - - - - <footer><div class="copyright"> - <p></p> -<p>Developed by Johannes Ranke.</p> -</div> - -<div class="pkgdown"> - <p></p> -<p>Site built with <a href="https://pkgdown.r-lib.org/" class="external-link">pkgdown</a> 2.0.7.</p> -</div> - - </footer> -</div> - - - - - - - </body> -</html> |